<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    .container {
      width: 500px;
      height: 500px;
      background-color: orange;

      display: flex;

      /* 
        flex-flow 是 flex-direction 和 flex-wrap 的简写形式
          取值：
          flex-direction: row | column | row-reverse | column-reverse;
          flex-wrap: nowrap | wrap | wrap-reverse;
          flex-flow: row wrap 
          flex-flow: row wrap-reverse;  
          flex-flow: column wrap;  
          flex-flow: column wrap-reverse;  
          
      */
      /* flex-direction: row-reverse;
      flex-wrap: wrap-reverse; */
      
      flex-flow: row-reverse wrap-reverse;     
    }

    .item {
      width: 120px;
      height: 120px;

      background-color: #f00;
    }
  </style>
</head>
<body>
  
  <div class="container">
    <div class="item item1">1</div>
    <div class="item item2">2</div>
    <div class="item item3">3</div>
  </div>

  <script src="./js/itemRandomColor.js"></script>
</body>
</html>